'04 WR450 Carb on '99 WR400
Posted July 16, 2005 - 03:28 PM
BTW, the reason I did this is because the slider keeps cracking on the original carb and I figured a newer design carb would solve the problem. The slider design is different (it seems to have some kind of damper in the throttle to keep it from slamming shut.)
Now that I'm typing this, I have no idea if the throttle stop has been cut so it looks like I need to take a look at it.
Posted July 16, 2005 - 03:40 PM
Here are the standard jet settings:
Main jet- '99 168 '04 165 - not a big deal
Main air jet - '99 75 '04 70- not a big deal
Pilot Jet- '99 42 '04 45- not a big deal
Needle- '99 DTM '04 DWR (pretty big difference here but it does have the same taper angle. '04 is fatter, so leaner but the clip setting height is 5 clips richer?? so it may just about even out)
Start jet- '99 60 '04 65 (this may also be one reason it was a little hesitant to start at first. May do some tweaking of this one)
Posted July 17, 2005 - 11:31 AM
I replaced the start jet with the one off my old carb and went from there. (65 down to a 60) It doesn't need the choke to start, which is a little puzzling, but then again, it's 92 degrees in my garage so it wasn't exactly a cold motor. Without the choke, it starts on the first kick. It runs better than it did with the old carb on and the front tire wants to lift up much easier now than it did before. Maybe I won't have the carb slider cracking issues any more. I think I like it.
Posted July 17, 2005 - 04:02 PM
I'm sticking with WR timing. Been down the YZ timing road before and I don't think it's ideal for tight trails like we often ride. Harder hitting but bottom end grunt (read: more clutch slipping) is the trade-off when you go to YZ timing. I've said this before, but I think Yamaha engineers know what they are doing with this bike and I try to leave it as close to stock as possible. (Notwithstanding the original carb design issues. At least they learned from their mistakes.)
Posted July 18, 2005 - 05:28 AM
i have a set of 450 cams, with the decomp, for sale. i'd much rather sell them as a set but if the right offer is made i'll part with just the one of them. pm me if you're interested in the cams.